I trained today, while doing triceps dips the guy next to me was on the lat pulldown machine. While I managed to complete three sets in about 2.5 minutes, he didn't perform a single set! I see this time and time again and people wonder why they're not making gains. In order to fatigue your muscles to a point where they are broken down and rebuilt stronger bigger, they need to be stressed sufficiently.

So having a 5 minute break on an isolation exercise or checking Facebook in between sets isn't going to get you results. If you really want to use your phone in the gym - set the timer to go off 40-50 seconds after your last set and see how much gains you make in your training!